By redesigning this proven powerhouse, O.S. is raising the bar for 1/10 scale racing engines. The enhancements may appear to be subtle, but they can make all the difference when it comes to taking the checkered flag.

• The Spec II boasts excellent mileage and an improved bottom end
• Holes machined into the aluminum outer head decrease overall weight to the bare minimum, and aid in cooling as well
• The crankcase and liner port have been designed to increase torque at low- to mid-speeds
• A special coating on the crankshaft reduces friction and wear
• Tungsten weights offer better balance at high rpm
• A newly designed cylinder head is 6mm shorter than previous heads for lower center of gravity

Stock Number: OSMG1991
Displacement: 0.128 cu in (2.1 cc)
Bore: 0.543 in (13.8 mm)
Stroke: 0.55 in (14.0 mm)
Practical RPM range: 5,000-44,000
Output: 1.75 hp @ 35,000 rpm
Weight w/o muffler: 7.8 oz (220 g)
Includes: 12F(B) carburetor, RP6 glow plug, exhaust seal ring, dust cap set and a 5.5mm red carb reducer